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The Neglected Brain, Part 1

Childhood neglect causes changes in the brain that trigger a cascade of physical and behavioral problems in adulthood. Credit: Kate Thompson

Editor’s Note: Neglect is by far the most common form of child maltreatment. Whether physical or emotional, benign or malicious, it alters the developing brain’s architecture and circuitry in profound and persistent ways that often lead to physical and behavioral problems throughout life. This is the first of a four-part series that explores the crippling, and yet reversible effects of childhood neglect on the brain and life of Danielle Goodwin. Read Part 2Part 3 and Part 4.

Danielle Goodwin, 36, was born in Great Falls, Montana to a pair of drug-addicted parents. She never met her biological father. Her mother married another man shortly after Danielle was born and had three more children before he died of a drug overdose. She then married one of Danielle’s father’s friends, and had another child. When they split up, Danielle’s mother married another one of his friends, had another baby. All in all, Danielle can count six stepfathers.

When Danielle was seven, her mother went into rehab and Danielle and her siblings went into foster care — three different placements, including one home where the foster mom would lock them out of the house all day. Danielle’s mother eventually returned from rehab and regained custody. “Anytime my mom was home and sober we would follow her anywhere she went and just cherish those moments,” recalls Danielle. Those moments were extremely rare. More often her mother would disappear for days, leaving the kids with whichever adult happened to be around at the time. Danielle’s childhood was a study in abuse and neglect.

Danielle’s story illustrates the dangerous and long lasting effects of neglect on the brain, the body and the spirit. How brain patterns set early in life lead to behaviors that can haunt a person into adolescence and beyond. Without intervention, the impacts of early childhood neglect are debilitating and contagious, spreading from parent to child for generations. But advances in brain science and in our understanding of trauma have begun to shed new light on the causes and effects of neglect and these insights offer hope to kids and adults who, like Danielle, were denied a safe, supportive upbringing. The latest science tells us that while the consequences of neglect are serious, they need not be permanent.

The invisible bruise

Neglect in families has long been the purview of sociologists and therapists. But neuroscientists are now on the trail. Their studies of brain development are beginning to explain why neglected kids and teens often develop mental health problems, struggle in school and are far more likely to become victims of violence and sexual abuse. Studies show how chronic neglect creates a brain that is laser-focused on survival, and the ways in which such a danger-obsessed brain works differently than one which has been exposed to positive human attention, comfort and support. The research also shows that, with the right inputs, dysfunctional brain patterns can be overcome.

Experts lump abuse and neglect together under the umbrella of “child maltreatment.” While they often occur together, abuse and neglect are fundamentally different experiences and they produce different consequences.

If “child abuse” is the term that collectively describes all the bad attention rained down on some unlucky children, “neglect” is the term for all the love, care, kindness and protection that so many more children never get. Neglect, a failure to act, can take many forms: physical, emotional, medical, educational. It is the most common type of child maltreatment by far, accounting for about four of the five calls to child protective service agencies nationally — more than calls about sexual, physical and emotional abuse combined.

Because neglect doesn’t leave a visible bruise, it can be harder to see, and harder to prove, and so is likely to be under-reported compared to abuse. Even so, in 2013 Child Protective Service workers in Washington state confirmed neglect in 4,194 of the 5,580 homes where some type of maltreatment was reported, according to the Partners for Our Children Data Portal. So, 75  percent of reported cases of child maltreatment in Washington State last year involved neglect. And that may be an underestimate.

National statistics indicate that every year, roughly 1 in 100 children experience some kind of maltreatment. But a recent study in the medical journal JAMA Pediatrics finds that the prevalence of mistreatment is actually much higher. Using statistics from the National Child Abuse and Neglect Data System Child File for the years 2004-2011, the study’s authors found that one in every 8 kids in the U.S. will be maltreated by age 18. The large discrepancy between the two figures arises from the fact that repeat cases of maltreatment were not being counted. “We might have skewed public perceptions of what maltreatment is,” says study co-author Hedy Lee, an assistant professor of sociology at the University of Washington. “These estimates show how prevalent the issue is and that we need to address this as a public health priority.”

Your brain on neglect

The key to understanding how neglect can have such long lasting impacts lies in understanding a bit about how the brain develops. Brain cells, called neurons, are elegant structures designed to receive and send electrical signals around the brain. Neurons consist of a cell body, a halo of dendrites and one long axon. The neuron cell body houses the nucleus and other machinery that runs the cell. Dendrites are short, profusely-branched extensions of the cell body that receive electrical inputs from surrounding cells. The axon is a long slender thread, like the tap root of a dandelion, that transmits electrical impulses to other cells. The axon is wrapped with a material called myelin which, like insulation around an electrical wire, helps to speed transmission.

Neuron and axon_Kate Thompson
Credit: Kate Thompson

Neurons don’t actually touch each other. When an electrical signal reaches the end of an axon, it must cross a microscopic gap, called a synapse, in order to stimulate the adjacent neuron. The signal makes this leap by triggering the release of molecules called neurotransmitters, which sail cross the synapse to propagate the signal in the adjacent and enable communication between cells.

Synapse_Illustration.jpg
Credit: Kate Thompson

At birth, most brain cells have already formed, but the brain continues to grow at a rate of one percent per day for the first three months of life. Some of this growth reflects the proliferation of dendrites and the rapid creation of synapses. In the infant brain, synapses proliferate at unfathomable speeds, with millions of connections forming second by second. In his 2011 bestseller, Incognito: The Secret Lives of The Brain, author and neuroscientist David Eagleman says that one cubic centimeter of brain tissue can contain more synapses than there are stars in the Milky Way.

The synaptic growth spurt is followed by another vital developmental process in which some synaptic connections strengthen and become inter-connected circuits, while others drop away. This synaptic building and “pruning” process is highly dependent on exposure to certain external interactions and experiences.

To an infant, a parent’s steady gaze is akin to sunlight falling on the leaves of a sapling. Babies mirror facial expressions in a “serve-and-return” fashion. Sensory cues like eye contact, cooing and smiling go back and forth between parent and child, like ping-pong balls across a net. If a parent fails to respond, the game stalls and development is disrupted, postponing the build out of neural circuits that makes it possible to crawl, walk and speak. A related theory of how neglect affects the developing brain is that sensory deprivation accelerates a natural pruning process designed to clear away connections that aren’t being used.

The Romanian orphan studies

Much of what we know about the impact of neglect on the brain comes from Romania, from one long-term and ongoing study called the Bucharest Intervention Project.

During his 24-year reign, the brutal Romanian dictator Nicolae Ceausescu banned birth control and abortion and cut social programs. He seemed to be encouraging struggling parents to have children then give them over to the state. When he was finally ousted from power in the 1989, and international reporters gained access to the country’s orphanages, they found more than 100,000 children living in concentration camp-like conditions. Babies were lined up next to each other, fed, changed and bathed like objects on an assembly line. At the time, brain science was still in its infancy, but reports were emerging that even the Romanian orphans who were getting plenty of food were not growing or thriving.

Concern for these children compelled a group of U.S. scientists, including Charles Nelson, at the Boston Children’s Hospital and Harvard Medical School, Nathan Fox from the University of Maryland and Charles Zeanah at the Tulane University Medical School, to work with the Romanian government to study the impact of the deprivation. Using Magnetic Resonance Imaging (MRI), the researchers tracked the brain development in children who grew up in orphanages. The researchers also trained — and helped to pay — foster families to take some of the children into their homes. Then they studied and compared the brain development of the two groups, both to each other and to a third group of children who were never institutionalized.

One of the study’s early findings was that institutionalized children have smaller brains. In addition, the branching of cell dendrites is simpler in neglected children, and the two fluid-filled ventricles in the center of their brains are markedly larger.

The brain is composed of grey matter and white matter. Generally speaking, grey matter refers to the various cell bodies in the brain. White matter refers to fibers, such as axons, that connect those cells — the brain’s transmission lines, if you will. The Bucharest study showed that kids who were placed in foster homes before the age of 2 were able to regain some brain matter, particularly white matter. (Scientists think that children don’t process information as quickly as adults because the white matter in their brains has not fully formed.)

The study also showed that while white matter volume increased when children were placed in enriched, caring environments, gray matter volume stayed the same. This finding suggests the existence of a “sensitive period” in development of the overall architecture of the brain, a period after which certain kinds of neural developments are no longer possible.

Later studies have confirmed and refined these early results, showing, for instance, that the cerebellum, one of the first areas of the brain to undergo rapid growth, is markedly smaller in neglected children. The cerebellum, located at the base of the brain, is the seat of motor skills. Current research shows that it also plays a role in regulating emotion, affection and behavior.

Scientists think the smaller cerebellums seen in neglected brains could be the result of the accelerated pruning process, says Dr. Katie McLaughlin, Assistant Professor of Psychology at the University of Washington and a member of the Bucharest Intervention team. “We have this architecture in place,” she explains. “If we’re not using it, we lose it, essentially. This accelerated pruning is likely to happen because the brain is not getting the expected environmental inputs that these circuits need to develop normally.”

Besides altering the basic architecture of the brain, neglect also affects the body’s stress response system, formally known as the Hypothalmic-Pituitary-Adrenal axis, or HPA. When activated, the HPA triggers the release of cortisol, a stress hormone. Cortisol plays an important role in daily life, helping our bodies release stored energy — in the form of glucose — into the bloodstream. It also helps regulate our diurnal rhythm. Cortisol levels are normally highest in the morning, and taper off to their lowest levels before bedtime.

Cortisol is also released in response to danger, igniting the “fight, flight or freeze,” responses that helped early humans evade predators. While releasing the stored glucose that’s necessary for escape, cortisol also shuts down other systems — like digestion or immune systems — that aren’t essential for immediate survival.

The “Still Face Experiment”

Stress for a baby is being tired, hungry, alone, in need of a diaper change, etc. In most cases, a mother, father or some other caretaker will tend to the baby’s needs and its stress levels will return to normal. When an infant’s cries for food or attention go unmet, however, its natural stress response continues to rev. When a baby’s needs go chronically unmet, the stress overdrive can lead to serious health consequences. Cortisol may be critical for survival in the wild, but chronically high levels of the hormone can retard bone formation, depress the immune system and increase the risk of diabetes. It also keeps the brain in a hyper-alert state that, over time, can lead to conditions such as Attention deficit Hyperactivity Disorder.

Dr. Edward Tronick is a professor of psychology at the University of Massachusetts in Boston, and an internationally-recognized researcher who studies infants, children and parenting. He has looked at the effects of post-partum depression on the emotional development of babies and children. His current work focuses on the health effects of infant stress.

“Babies,” explains Dr. Tronick in this “Still Face Experiment” video,  “. . . are extremely responsive to the emotions and the reactivity and the social interaction that they get from the world around them.” The “Still Face Experiment” explores what happens when those emotions and reactions and interactions stop.

The video begins with a loving mother staring into her baby girl’s eyes, smiling and following the contented baby’s cues as she points and laughs. “They’re working to coordinate their emotions and their intentions,” explains Tronick in the video. Then researchers have the mother stop smiling at her baby, stop reacting and instead present a flat, unresponsive expression. The baby immediately picks up on the change and after trying — and failing — to engage her mother, she begins to squirm and squeal and cry.

“[Babies] feel the stress,” says Tronick in the video. The situation is “a little bit like the good, the bad and the ugly: The good is that normal stuff that we all do with our kids. The bad is when something bad happens, but the infant can overcome it. After all, when you stop the ‘still face’ the mother and the baby start to play again. The ugly is when you don’t give the child any chance to get back to the good … and they’re stuck in that really ugly situation.”

The “Still Face” video illustrates what happens when a mother fails to comfort her child — for two minutes. For children like Danielle Goodwin, the failure to respond, the “ugly” to use Edward Tronick’s word, plays out across all the years of childhood, through adolescence and into early adulthood.

As a baby, Danielle was starved for eye contact and cooing and cuddling. One of her mother’s many boyfriends would tell her, “You’ve got to give your mom space,” she recalls. To underscore his point he bought a Mazda Miata, a two-seater. As the oldest of her drug-addicted mother’s six children, Danielle was often the only one sober enough to care for her siblings. By age 10, she had adult responsibilities. After fifth grade, Danielle stopped attending school. No one seemed to notice or care.

Abusive men cycled in and out of the family’s home; that is, when they had one. Danielle’s family was often homeless, bouncing from Montana to Washington, Canada, Idaho and back again. By the time she was 13, Danielle was being sexually exploited on a regular basis and shooting heroin with her mother. It didn’t seem strange, she says. It was what she knew. “We were more like friends, or so I thought,” says Danielle about her mother. “It was a very unhealthy relationship.”

By age 14, Danielle was pregnant, raped by one of her mother’s boyfriends. Her mother too had been sexually abused from the time she was a young girl. When Danielle delivered her baby at the University of Washington hospital, tests showed drugs in the newborn’s system. That finding flagged Danielle for intervention, and landed both her and her baby in a foster home. Like her first foster care experience, this one did nothing to help Danielle cope with her situation as an unwed, teenage, drug-using mother. There was no counseling or parenting classes, and no help with her substance abuse problem. “They knew the circumstances that landed me in the system,” she says. “I was placed in a home without any services.”

Danielle would eventually run away to the streets and turn tricks to survive. She would grow addicted to heroin and cocaine, and come under the sway of a violent pimp. By age 28, she had given birth to five children, and lost all of them to the state. She was repeating the familiar family pattern.

Tomorrow, Part 2: How essential life skills such as wariness of strangers, impulse control and the ability to distinguish right from wrong become casualties of a neglectful childhood. Read Part 2, Part 3 and Part 4.

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